Surface regulation of Cu-based catalysts to adjust the selectivity and promotion strategy of electrochemical reduction of CO2 to C2 products

Electrochemical CO2 reduction reaction (CO2RR) holds great promise as a method for converting CO2 into valuable fuels and chemical raw materials using renewable energy. Cu, a key element in CO2RR, has garnered significant attention for its ability to transform CO2 into high-value fuels. In recent years, there has been a widespread focus on understanding various factors influencing the catalytic performance of copper, including crystal orientation, morphology, and size. Additionally, the presence of additive elements has been found to impact the reaction process through different mechanisms, influenced by concentration and binding forms. The catalytic design process is complicated by the intricate interplay of these factors, making it challenging to isolate individual effects. In this review, we examine the recent advancements in catalyst design, focusing on the influence of the surface structure of metallic Cu on the selectivity of CO2RR. Additionally, we provide a summary of how additives contribute to enhancing catalyst performance. Novel concepts are put forth for the design of Cu-based catalysts, with the aim of overcoming the current selectivity challenges. To begin, we elucidate the impact of surface structure design on CO2RR selectivity, with a specific emphasis on ethylene and ethanol production. Subsequently, we highlight the remarkable contributions of bimetallic catalysts to the selectivity of CO2RR. Finally, we propose the incorporation of cooperative and confinement effects as a strategy to modulate the selectivity of CO2RR. We look ahead to the future prospects of CO2RR, anticipating further breakthroughs in this field.